Steering linkage



March 28, 1939. M. A. THORNE 2,152,506

STEERING LINKAGE Filed May 10, 1937 Patented Mar. 28, 1939 UNITED STATES PATENT oFFlcE STEERING maar Application May 10, 1937, Serial No. 141,814

3 Claims. (Cl. 28o-95) This invention relates to vehicle steering mechanism and more particularly to an improved system of motion transmitting linkage.

An object of the invention is to provide linkage which is especially adapted for use with independently sprung steerable wheels of the type wherein each wheel spindle is carried on the end of a pivoted suspension arm, the axis of which is diagonally related to the longitudinal center line of the vehicle, with a load carrying coil spring between the arm and chassis frame and which linkage is so related to the axis oi the suspension arm as to minimize disturbance of steering geometry.

A further object oi' the invention is to provide steering linkage which provides ample clearance for the frame mounted engine and other units of the vehicle.

Other objects and advantages of the invention will become apparent during the course of the following speciilcation having reference to the accompanying drawing wherein Figure l is a top plan view of a iront portion of a vehicle chassis and running gear embodying the invention; and Figures 2 and 3 are enlarged views taken substantially on lines 2-2 and 3 3, respectively, of Figure 1.

The chassis of the vehicle comprises the side frame members I and 2 together with a iront 30 cross member 3. Pivoted in suitable brackets near the center of the front member 3 and on divergently related axes are a pair oi outwardly extending suspension arms 4 and 5 in the ends of which are mounted steering knuckles for the road 35 wheels 6 and l, respectively. At an intermediate point each lever provides a seat for one end oi a coil spring, shown by dotted lines at 8 8, the other end of which is seated on the chassis frame and through which the load is transferred. At its upperend each wheel knuckle is connected to an arm 9 which constitutes the operating lever for a shock absorber II), one for each independently sprung wheel.

'I'he wheel suspension referred to is substantially that being used on Oldsmobile automobiles and the steering linkage ordinarily used with this suspension involves a pair of tie rods joined at their outer ends to the wheels and at their inner ends to a bell crank lever pivotally mounted on 50 the frame cross member 3 and adapted for connection with the usual steering column assembly. 'I'he conventional linkage has been found to interfere with the free relative disposition of the parts especially the wheel suspension system and the engine which drives the vehicle. In other words,

if these parts are brought close together there Is insufiicient clearance between the engine oil pan and the swinging lever and with this in mind it is proposed here to eliminate the bell crank and its mounting on the frame and in lieu thereof to- 5 Join the adjacent ends of the tie rods to a transverse link which can be supported and guided in the path below the oil pan limits. l

Accordingly the drawing shows the spaced wheel steering arms II and I2 pivotally connected 10 by suitable ball joints with the remote ends of v the tie rods I3 and I4 arranged end to end and joined by ball and socket;l connections at their adjacent ends to a forwardly extending plate or. ear I5 welded or otherwise secured to a transverse l5 link I6. One end of the link I6 is pivotally connected to the swinging pitman arm I1 forming a part of the steering assembly column'- I8 which is oiset to one side of the longitudinal center line and is secured to the frame member I. The other 20 end of the link I6 is pivoted to an idler lever I8 mounted on a frame bracket 2l) carried by the side member 2 of the chassis frame. 'Ihus the transverse link I8 is supported and guided for movement with the pitman arm Il and in turn 25 supports the adjacent ends of the tie rods I3 and I4 and through this linkage 'the steering wheels 6 and 'I are turned in unison under control of the usual steering wheel forming a part of the steering column I8.

It will be noted particularly from Figure 1 lthat the pivotal mountings for the inner ends of the tie rods normally are positioned adjacent the point of convergence of or are alined with the axes of the swinging levers 4 and i and because 35 of this relation, relative movement between the chassis frame and suspension arms occurs without displacing either of the spaced and independently suspended pivoted steering wheel knuckles during general straight ahead travel. o

I claim:

1. In combination, a frame, a pair of independent wheel suspension levers mounted on the frame on intersecting axes, steerable wheels on said levers, a pair of wheel connected rods ex- 45 tending inwardly toward the point of intersection of said axes, a motion transmitting link operably connected to said rods at spaced points normally aligned, respectively, with the axis of an associated wheel suspension lever and disposed trans- 5 versely of the frame, an idler lever mounted on the frame to support one end ofsaid link, and a steering gear pitman arm connected to the opposite end oi said link.

2. In a motor vehicle, a frame, an oifset steeru ing column assembly having an operating member, a transverse link connected at one endto said member, guide means supporting the other end of the link, a pair oi' outwardly extending tie rods joined at their inner ends to an intermediate portion o! said link, steerable wheels connected to the outer ends of the rods, and independent wheel suspension arms hinged to the frame on diagonally related axes converging toward said intermediate portion oi' therlink in coaxial relation with the joint axes at the inner ends of the tie rods. e

3. In a motor vehicle having a frame, indeto said projected coupling plate on spaced axes normally coincident with the pivotal mounting axes of their respective associated wheel assem- 10 blies.

MAURICE A. THORNE. 

